A number of applications such as aerospace, automotive and industrial control utilize network systems such as multimedia entertainment, communications, process control and diagnostic systems. As these systems become more complex, a need arises for additional devices to communicate with one another or a central controller or the like. Network systems have been developed to provide a common communications path between network devices. In aerospace and automotive applications, for example, a network system may be utilized to monitor various components and to collect diagnostic and status information such as that relating to the strain, acceleration, pressure and/or temperature. In another example, a network system may be utilized to support communications and the delivery of multimedia information to occupants in an aerospace or automotive application, or for use in process control applications that could be applied to a system such as a vehicle.
Many traditional systems have long analog wiring that may be susceptible to undesirable noise and signal degradation. Even current networked systems developed to shorten the analog wiring still use complicated protocols requiring high-level processors that limit miniaturization and thus limit device locations which can still result in long analog wiring. Further, high-level protocols may introduce overhead into the messages on a bus that may severely limit the number of data samples that can be transmitted on the bus, the latency at which data can be transmitted or delivered, or the time-determinism of the data sampling and delivery. These networks also generally do not support acquisition and control, and they typically only support networks that extend over relatively short lengths. Further, these networks typically have bulky network device interfaces, slow network data rates and/or a low network device count. Additionally, many computer systems that include digital networks do not operate in a time-deterministic manner, and as such, lack the capability to schedule a trigger command to the network components that repeats or is interpreted and executed with any precision timing.
A protocol and digital network structure have been developed to address a number of shortcomings of conventional digital networks. This protocol and digital network structure are described, for example, in U.S. Pat. No. 6,708,239, entitled: Network Device Interface for Digitally Interfacing Data Channels to a Controller via a Network, issued on Mar. 16, 2004, and U.S. Patent Application Publication No. 2002/0112070, entitled: Bus Controller for Digitally Controlling Remote Devices via a Common Bus, published on Aug. 15, 2002, the contents of both of which are incorporated herein by reference. Although this protocol and network structure offers many advantages over many conventional digital networks, it is typically desirable to make further improvements.